Fagineura glabella Hara, sp. nov.

(Figs 5D–H, 6L, 7I, O, 8E, N, V, 9H, P, 10J, 13D, E)

Description: female. Length 7.0–9.0 mm (holotype 9.0 mm). Yellowish red (Figs 5D–H). Head black on ocellar area, medial or ventromedial area of occiput and antenna, and yellow on face, malar space, labrum, mandible except apex dark reddish brown, maxilla except for black part of stipes and labium except for black prementum. Thorax with tegula yellow; mesoscutum black on most of lateral mesoscutal lobe and posterolateral hollow; mesoscutellum very often centrally black; mesopostnotum black, sometimes medially narrowly yellow or brown; metanotum mostly black, with metapostnotum often widely yellowish medially; prosternum and propleuron mostly yellow to entirely black respectively; postspiracular sclerite yellow; epicnemium yellow, sometimes ventrally darkened; mesepsisternum widely black ventrally; anepimeron and metepisternum except for dorsal area black. Legs black; trochanters and their adjacent areas pale yellow; tibiae and tarsi dark brown to black, basally yellowish or brownish. Wings colorless transparent; veins brown to black; stigma brown, marginally darkened. Abdomen dark brown to black on medial parts of basal four terga to most of dorsum, sterna, anterior part of valvifer 2 and valvula 3; apical sterna sometimes medially yellow; cercus brown, usually darkened apically.

Head in dorsal view with length behind eye 0.5–0.6 × eye length (Fig. 6L); length behind lateral ocellus 2.6–3.7 × length of lateral ocellus. OOL:POL:OOCL 0.9–1.1:1.0:1.1–1.3. Frontal area with lateral ridge weak and anterior ridge well developed; frontal field with long lateral convexity, sometimes with slight median convexity. Distance between eyes at anterior tentorial pit 1.2–1.3 × major axis of eye. Inner edges of eyes nearly parallel (Fig. 5G). Malar space 0.4–0.5 × as long as median ocellus width. Antenna 2.4–2.7 × as long as head width (Fig. 5D); flagellum tapered; flagellomere 1 0.7–0.8 × as long as major axis of eye; flagellomere 2 1.1–1.2 × as long as flagellomere 1. Mesepisternum distinctly expanded beside postspiracular sclerite. Hind tibia with posterior spur 0.8–1.0 × as long as apical breadth of tibia in lateral view. In forewing, crossvein 2r-rs absent (one female has incomplete crossvein 2r-rs in the left forewing).

Valvula 3 in dorsal view about 1.5–2 × as wide as cercus, apically concave (Fig. 9H), in lateral view apically rounded or angulated, with dorsal edge straight and ventral edge rounded (Fig. 9P). Lance with dorsal edge slightly rounded (Fig. 10J). Lancet with radix 0.5–0.6 × as long as lamnium (Figs 13D, E); lamnium with 18–21 annuli; basal annuli slightly sinuous; middle and apical annuli straight and oblique or perpendicular; annulus 1 with vestigial ctenidium dorsally or without ctenidium; ctenidia widely separated from each other, except for ctenidium of annulus 1 each expanded dorsally and consisting of some irregular transverse rows of setae; basal serrulae with anterior slope shorter than posterior slope.

Head and thorax with punctures minute or inconspicuous; interspaces between punctures generally smooth. Postocellar area, mesoscutum (Fig. 8E) and mesoscutellum widely or mostly glabrous. Mesoscutum with posterolateral hollow with rugose and granular microsculpture. Mesopostnotum with rugose and granular microsculpture, medially smooth. Metapostnotum mostly smooth. Postspiracular sclerite glabrous, rarely with one or two setae. Mesepisternum widely or narrowly glabrous beside postspiracular sclerite (Fig 8N). Katepimeron extensively covered with setae. Abdomen imbricately microsculptured, with punctures inconspicuous.

Male. Unknown.

Material examined. Holotype: ♀, “ JAPAN, HONSHU, Hyogo Pref., Kobe, Kidu, 28. IV. 2012, H. Yoshida ” (Figs 5D–H, 6L, 7I, O, 8E, N, V, 9H, P, 10J, 13D) . Paratypes: JAPAN: HONSHU: 1♀, Tochigi Pref., Nakagawa, Koisago, coll. larva on Quercus acutissima 17. V. 2013, mat. 24. V., em. 35. III. 2014, S. Ibuki; 11♀, Tochigi Pref., Sano, Shiroyama-koen, coll. larvae on Quercus acutissima 12. V. 1978, em. 3–7. IV. 1979, T. Saito; 1♀, Chiba Pref., Ichikawa, Konodai, coll. larva on Quercus sp. 7 . V. 1950, em. 5. IV. 1951; 1♀, Tokyo Met., Setagaya, Nakahara, 28. IV. 1935 ; 1♀, Kanagawa Pref., Yokohama, Nokendo, 10. IV. 1998, K. Kubo; 1♀, Yamanashi Pref., Nirasaki, Shinpu, 25. IV. 1931, H. Masuda; 1♀, Osaka Pref., Ikeda, Mt. Satsuki-yama, 18. IV. 2013 , R. Matsumoto; ― KOREA: 1♀, Gangwon-do, Mt. Odaesan, Pukdae-sa, 1300m, 30. V. 1991, A. Shinohara; 1♀, same data but 29. V. – 1. VI. 1996; 2♀, same data but 30. V. 2008 (Fig. 13E); 2♀, Gyeonggi-do, Suwon, 27. IV. 1927 , K, Sato; 2♀, same data but 4. V. 1927; 2♀, same data but 5. V. 1931. ― LOCALITY UNKNOWN: 2♀, “312”, “K. Sato Collection” .

Etymology. The specific name is an adjective, meaning hairless or smooth, and comes from the widely hairless and smooth mesonotum.

Distribution. Japan (Honshu), Korea.

Life history. Host plants: Fagaceae: Quercus acutissima Carruth.

This species has univoltine life cycle. In lowlands of Honshu, Japan, adults occur in middle and late April and larvae occur in May.

Remarks. This species is similar to F. quercivora in color, but they are distinguished as stated in the key. Their lancets are also different. The ctenidum of the annulus 2 is developed in F. glabella (Figs 13D, E) but rudimentary in F. quercivora (Figs 13A–C).